<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>

</body>

</html>
<script>
    // 实现json对象的深拷贝
    var obj = { name: '李李', age: 18, sex: 22, hobby: ['打篮球', '乒乓球', '跳舞'] };
    function copyObj(obj) {
        var obj2 = Array.isArray(obj) ? [] : {};
        // 遍历obj，key是属性名, obj[key]是属性值
        for (var key in obj) {
            //判断key属性的值是否是引用类型, 如果是, 递归处理该属性的值
            if (typeof obj[key] == 'object') {
                obj2[key] = copyObj(obj[key])
            } else {
                //key属性的值不是引用类型, 直接拷贝该属性的值
                obj2[key] = obj[key];
            }
        }
        return obj2;
    }
    //深拷贝
    var obj2 = copyObj(obj);
    obj.hobby.push('打游戏');
    console.log(obj, obj2);
</script>